Field
The described technology generally relates to a display device and a method of manufacturing the same.
Description of the Related Technology
A display device, such as a liquid crystal display (LCD), an organic light-emitting diode (OLED) display, and an electrophoretic display, includes an electric field generating electrode and an electro-optical active layer. For example, an OLED includes an organic emission layer as the electro-optical active layer, and the field generating electrode is connected to a switch such as a thin film transistor to receive a data signal, and the electro-optical active layer converts the data signal to an optical signal to display an image.
OLED displays have favorable characteristics such as low power consumption, rapid response rate, high viewing angles, and high contrast ratio.
rather than using color filters as with LCD technologies, the display device includes sets of multi-color self-emitting sub-pixels such as red pixels, blue pixels, green pixels, and white pixels, and can express a full color gamut by combining light from the sub-pixels. Each pixel includes a thin film transistor and at least one field generating electrode connected thereto.
When the display device employs a glass substrate that is heavy and easily broken, there are limitations in its portability and ability to implement a cost-effective large-scale screen display. Hence, OLED displays use at least one flexible substrate as the base substrate because they are lightweight, resistant to impact, and flexible. The flexible substrate is typically formed of a plastic material such as polyimide.
Flexible substrates are very thin and have good flexible characteristics, but they can be easily damaged during manufacturing of the display device. Therefore, the flexible substrate undergoes a thin film transistor process while attached to a carrier substrate, and the carrier substrate is then separated from the flexible substrate. In this case, a sacrificial layer for easily separating the carrier substrate from the display device can be used during the process for manufacturing process.
However, the process for thin film coating the flexible substrate or for bonding the carrier substrate and the flexible substrate, applies heat (thermal treatment), which increases manufacturing time and production costs. Further, the flexible substrate can be deformed by a heat expansion coefficient difference between the carrier substrate and the flexible substrate during the heat treatment.
The above information disclosed in this Background section is only to enhance the understanding of the background of the described technology and therefore it can contain information that does not constitute the prior art that is already known in this country to a person of ordinary skill in the art.